package org.mikeliu.exp2.homework3;

import java.util.Scanner;

class Circle{
    private double radius;  
    public Circle() {
         radius=1;
    }

    public Circle (double radius){
         this.radius=radius;
    }
    
    public double getRadius() {
             return this.radius;
    }

    public void setRadius(double radius) {
             this.radius=radius;
    }

    public double getArea() {
         return Math.PI*radius*radius;
    }
    public double getLength() {
         return 2*Math.PI*radius;
    }
}

public class Homework3 {
	public static void main(String[] args) {
		Scanner scanner=new Scanner(System.in);
		Circle circle1 = new Circle();
		System.out.println(circle1.getRadius()+" "+circle1.getArea());
		Circle circle2 = new Circle(25);
		System.out.println(circle2.getRadius()+" "+circle2.getArea());
		circle2.setRadius(100);
		System.out.println(circle2.getRadius()+" "+circle2.getArea());
		}
}
